Lake Natron, Tanzania
Microorganisms that thrive on salt flock to this lake, producing a red pigment which colorizes the water. The lake contains so much salt that if other animals took a dip in the water they would calcify, essentially turning to stone.
Underwater Waterfall, Mauritius Island
Yep, that's a waterfall under the ocean's surface. Strong currents force sand from the shores of Mauritius into the chasm.
Salar de Uyni, Bolivia
The Salar was created when several prehistoric lakes joined into one, creating the world's largest mirror from its salty surface. It's so reflective it can calibrate satellites.
Sea of Stars, Vaadhoo Island, Maldives
This sea looks perfectly normal during the day; however, once nightfall hits, marine microbes called phytoplankton make the water sparkle like a starry sky.
This actually isn't a surrealist painting — it's the "dead valley." Here, the trees stand against the highest sand dunes in the world.
Turquoise Ice, Lake Baikal, Russia
This freshwater lake is so clear that when it freezes in the winter you can see 130 feet below the surface, which creates the turquoise glow at the top.
Antelope Canyon, Arizona, United States
The deep but narrow crevices of this canyon were formed by millions of years of flowing water. Because limited light can reach the interior of the canyon, the walls appear to be different colors.
Zhangye Danxia Landform, Gansu, China
24 million years' worth of mineral deposits in these red sandstone formations create the colorful landscape. Rain and wind chipped away at it, forming the spectacular shapes.
Tunnel of Love, Klevan, Ukraine
The romantic tunnel was shaped by trains once traveling this route three times a day. The trains no longer run, so the spot is free for starry-eyed strolls.
Skaftafell Ice Cave, Iceland
Although not a permanent structure, this ice cave forms at the edge of glaciers when flowing water melts a hole into the glacier. The ice absorbs all light except for blue, creating the indigo glow.
Reed Flute Caves, China
The breathtaking stalactites, stalagmites and pillars were created through water erosion beautifully decorating this 240-meter-long cave.
Glowworm Caves, Waitomo, New Zealand
Glowworms hang from this cave's walls, creating the twinkling light effect.
Yuanyang County, China
Farming is to thank for the enchanting landscapes of Yuanyang county. Rice fields cover the Ailao Mountains.
Lake Hillier, Australia
Algae and bacteria produce the pink dye that decorates this lake. Although very bright, the water is safe for wildlife and humans.
Grand Prismatic Hot Spring, Wyoming
The pigmented microbes that grow on the edges of the water color the Grand Prismatic Hot Spring.
Pamukkale Hot Springs, Turkey
As chilly as this photo looks, these are not slabs of ice, but hot springs that took millions of years to form.
Caño Cristales River, Colombia
Dubbed "the most beautiful river in the world," the extremely varied flora and fauna color the body of water red, yellow, green and black.
Fly Geyser, Nevada
When a well was drilled but left uncapped, the Fly Geyser was created.
Tianzi Mountains, China
Look familiar? These extremely tall and thin mountains were used in "Avatar."
Sentinels of the Arctic, Finland
These magnificent ice sculptures are actually trees covered in ice. The temperature here can fall below -40 degrees Fahrenheit.
Patagonia Marble Caves, Chile
The marbled swirls on the walls of this cave were formed by thousands of years of crashing waves.
Giant's Causeway, Northern Ireland
Approximately 50-60 million years ago, an intense volcanic eruption created these symmetrical columns.
Underwater River, Cenote Angelita, Mexico
Beneath the water of Cenote Angelita lies another body of water — a flowing river. Because the river's water is filled with hydrogen sulfate (a heavier substance than salt water), the water sinks to the bottom, creating an underwater river.
Naica Mine, Mexico
This Mexican silver mine is filled to the brim with crystals as large as 50 feet long and 4 feet wide.
The isolated highlands are filled with glaciers, craters, lakes and geysers, making it the perfect place to see the aurora borealis.
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